Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

Omnath, Locus of Mana

You don't lose unspent green mana as steps and phases end.
Omnath, Locus of Mana gets +1/+1 for each unspent green mana you have.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Crackle with Power

Crackle with Power deals five times X damage to each of up to X targets.

Exocrine

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Bio-plasmic Barrage — When Exocrine enters, it deals X damage to each player and each other creature.

Forest

Dictate of Karametra

Flash
Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Erebos's Intervention

Choose one —
• Target creature gets -X/-X until end of turn. You gain X life.
• Exile up to twice X target cards from graveyards.

Klauth's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Breathe Flame — Klauth's Will deals X damage to each creature without flying.
• Smash Relics — Destroy up to X target artifacts and/or enchantments.

Aberrant

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Trample
Heavy Power Hammer — Whenever Aberrant deals combat damage to a player, destroy target artifact or enchantment that player controls.

Rosheen Meanderer

{T}: Add {C}{C}{C}{C}. Spend this mana only on costs that contain {X}.

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

Savage Lands

Savage Lands enters tapped.
{T}: Add {B}, {R}, or {G}.

Song of Totentanz

Create X 1/1 black Rat creature tokens with "This creature can't block." Creatures you control gain haste until end of turn.

Zhur-Taa Druid

{T}: Add {G}.
Whenever you tap Zhur-Taa Druid for mana, it deals 1 damage to each opponent.

Shivan Devastator

Flying, haste
Shivan Devastator enters with X +1/+1 counters on it.

Ignoble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {B}, {R}, or {G}.

Vexing Shusher

This spell can't be countered.
{R/G}: Target spell can't be countered.

Magus of the Vineyard

At the beginning of each player's first main phase, that player adds {G}{G}.

Magus of the Candelabra

Genesis Hydra

When you cast this spell, reveal the top X cards of your library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield. Then shuffle the rest into your library.
Genesis Hydra enters with X +1/+1 counters on it.

Rootbound Crag

Rootbound Crag enters tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

Staff of Domination

{1}: Untap Staff of Domination.
{2}, {T}: You gain 1 life.
{3}, {T}: Untap target creature.
{4}, {T}: Tap target creature.
{5}, {T}: Draw a card.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

Power Surge

At the beginning of each player's upkeep, Power Surge deals X damage to that player, where X is the number of untapped lands they controlled at the beginning of this turn.

War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.

Sting, the Glinting Dagger

Equipped creature gets +1/+1 and has haste.
At the beginning of each combat, untap equipped creature.
Equipped creature has first strike as long as it's blocking or blocked by a Goblin or Orc.
Equip {2}

Rockfall Vale

Rockfall Vale enters tapped unless you control two or more other lands.
{T}: Add {R} or {G}.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Sol Ring

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Spire Garden

Spire Garden enters tapped unless you have two or more opponents.
{T}: Add {R} or {G}.

Apocalypse Hydra

Apocalypse Hydra enters with X +1/+1 counters on it. If X is 5 or more, it enters with an additional X +1/+1 counters on it.
{1}{R}, Remove a +1/+1 counter from Apocalypse Hydra: It deals 1 damage to any target.

Command Tower

Lavalanche

Lavalanche deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls.

Seeker of Skybreak

Unbound Flourishing

Whenever you cast a permanent spell with a mana cost that contains {X}, double the value of X.
Whenever you cast an instant or sorcery spell or activate an ability, if that spell's mana cost or that ability's activation cost contains {X}, copy that spell or ability. You may choose new targets for the copy.

Zhur-Taa Ancient

Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Yurlok of Scorch Thrash

Vigilance
A player losing unspent mana causes that player to lose that much life.
{1}, {T}: Each player adds {B}{R}{G}.

Lair of the Hydra

If you control two or more other lands, Lair of the Hydra enters tapped.
{T}: Add {G}.
{X}{G}: Until end of turn, Lair of the Hydra becomes an X/X green Hydra creature. It's still a land. X can't be 0.

Savageborn Hydra

Double strike
Savageborn Hydra enters with X +1/+1 counters on it.
{1}{R/G}: Put a +1/+1 counter on Savageborn Hydra. Activate only as a sorcery.

Heartbeat of Spring

Tyvar's Stand

Target creature you control gets +X/+X and gains hexproof and indestructible until end of turn. (A creature with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Mountain

Solphim, Mayhem Dominus

If a source you control would deal noncombat damage to an opponent or a permanent an opponent controls, it deals double that damage to that player or permanent instead.
{1}{R/P}{R/P}, Discard two cards: Put an indestructible counter on Solphim, Mayhem Dominus. ({R/P} can be paid with either {R} or 2 life.)

Citadel of Pain

At the beginning of each player's end step, Citadel of Pain deals X damage to that player, where X is the number of untapped lands they control.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Garenbrig Growth

Return target creature or land card from your graveyard to your hand. (Then exile this card. You may cast the enchantment later from exile.)

Virtue of Strength

If you tap a basic land for mana, it produces three times as much of that mana instead.

Virtue of Strength // Garenbrig Growth

Kessig Wolf Run

{T}: Add {C}.
{X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Mana Flare

Hungering Hydra

Hungering Hydra enters with X +1/+1 counters on it.
Hungering Hydra can't be blocked by more than one creature.
Whenever Hungering Hydra is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

Belbe, Corrupted Observer

At the beginning of each postcombat main phase, the active player adds {C}{C} for each of your opponents who lost life this turn. (Damage causes loss of life.)

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Helix Pinnacle

Shroud (This enchantment can't be the target of spells or abilities.)
{X}: Put X tower counters on Helix Pinnacle.
At the beginning of your upkeep, if there are 100 or more tower counters on Helix Pinnacle, you win the game.

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Mana Reflection

If you tap a permanent for mana, it produces twice as much of that mana instead.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent or discards a card.

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters, you may pay 2 life. If you don't, it enters tapped.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters tapped unless you control two or more basic lands.

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Victory Chimes

Untap Victory Chimes during each other player's untap step.
{T}: A player of your choice adds {C}.

Awaken the Woods

Create X 1/1 green Forest Dryad land creature tokens. (They're affected by summoning sickness.)

Stoneshaker Shaman

At the beginning of each player's end step, that player sacrifices an untapped land.

Sword of the Paruns

As long as equipped creature is tapped, tapped creatures you control get +2/+0.
As long as equipped creature is untapped, untapped creatures you control get +0/+2.
{3}: You may tap or untap equipped creature.
Equip {3}

Overabundance

Whenever a player taps a land for mana, that player adds one mana of any type that land produced, and Overabundance deals 1 damage to the player.

Ziatora's Proving Ground

({T}: Add {B}, {R}, or {G}.)
Ziatora's Proving Ground enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Pest Infestation

Destroy up to X target artifacts and/or enchantments. Create twice X 1/1 black and green Pest creature tokens with "When this creature dies, you gain 1 life."

Electrodominance

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

Damnable Pact

Target player draws X cards and loses X life.

Swamp

Reap the Past

Return X cards at random from your graveyard to your hand. Exile Reap the Past.

Nyxbloom Ancient

Trample
If you tap a permanent for mana, it produces three times as much of that mana instead.

Umbral Mantle

Equipped creature has "{3}, {Q}: This creature gets +2/+2 until end of turn." ({Q} is the untap symbol.)
Equip {0}

Deathcap Glade

Deathcap Glade enters tapped unless you control two or more other lands.
{T}: Add {B} or {G}.

Jaya's Immolating Inferno

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Jaya's Immolating Inferno deals X damage to each of up to three targets.

Green Sun's Twilight

Reveal the top X plus one cards of your library. Choose a creature card and/or a land card from among them. Put those cards into your hand and the rest on the bottom of your library in a random order. If X is 5 or more, instead put the chosen cards onto the battlefield or into your hand and the rest on the bottom of your library in a random order.

Animist's Awakening

Reveal the top X cards of your library. Put all land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap those lands.

Leyline Tyrant

Flying
You don't lose unspent red mana as steps and phases end.
When Leyline Tyrant dies, you may pay any amount of {R}. When you do, it deals that much damage to any target.